Blowout preventer annular

ABSTRACT

A packer assembly for an annular blowout preventer includes an annular packer, a plurality of inserts, and a support. The plurality of inserts is arranged circumferentially about the annular packer and configured to move radially inward to enable the packer assembly to move from an open position in which the packer assembly enables fluid flow through a central bore to a closed position in which the packer assembly blocks fluid flow through the central bore. The support is positioned below the plurality of inserts with respect to a height of the packer assembly and is configured to block at least a portion of the annular packer from moving into an opening extending through the annular packer in the closed position.

BACKGROUND

This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

An annular blowout preventer (BOP) is installed on a wellhead to seal and control an oil and gas well during drilling operations. A drill string may be suspended inside an oil and gas well from a rig through the annular BOP into the well bore. During drilling operations, a drilling fluid is delivered through the drill string and returned up through an annulus between the drill string and a casing that lines the well bore. In the event of a rapid invasion of formation fluid in the annulus, commonly known as a “kick,” the annular BOP may be actuated to seal the annulus and to control fluid pressure in the wellbore, thereby protecting well equipment disposed above the annular BOP. The construction of various components of the annular BOP can affect operation of the annular BOP.

BRIEF DESCRIPTION OF THE DRAWINGS

Various features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying figures in which like characters represent like parts throughout the figures, wherein:

FIG. 1 is a block diagram of a mineral extraction system, in accordance with an aspect of the present disclosure;

FIG. 2 is a cutaway perspective side view of an embodiment of an annular BOP in an open position that may be used in the mineral extraction system of FIG. 1, in accordance with an aspect of the present disclosure;

FIG. 3 is a cross-sectional side view of an embodiment of the annular BOP of FIG. 2 in a closed position, in accordance with an aspect of the present disclosure;

FIG. 4 is a perspective view of an embodiment a packer assembly that may be used in the annular BOP of FIGS. 2 and 3, in accordance with an aspect of the present disclosure;

FIG. 5 is a perspective view of an embodiment of inserts of the packer assembly of FIG. 4, in accordance with an aspect of the present disclosure;

FIG. 6 is a perspective view of an embodiment of the packer assembly that may be used in the annular BOP of FIGS. 2 and 3, in accordance with an aspect of the present disclosure;

FIG. 7 is a perspective view of an embodiment of the packer assembly of FIG. 6, in accordance with an aspect of the present disclosure;

FIG. 8 is a perspective view of an embodiment of inserts of the packer assembly of FIGS. 6 and 7, in accordance with an aspect of the present disclosure; and

FIG. 9 is a perspective view of an embodiment of the packer assembly that may be used in the annular BOP of FIGS. 2 and 3, in accordance with an aspect of the present disclosure.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

One or more specific embodiments of the present disclosure will be described below. These described embodiments are only exemplary of the present disclosure. Additionally, in an effort to provide a concise description of these exemplary embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

When introducing elements of various embodiments, the articles “a,” “an,” “the,” “said,” and the like, are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” “having,” and the like are intended to be inclusive and mean that there may be additional elements other than the listed elements. The use of “top,” “bottom,” “above,” “below,” and variations of these terms is made for convenience, but does not require any particular orientation of the components relative to some fixed reference, such as the direction of gravity. The term “fluid” encompasses liquids, gases, vapors, and combinations thereof.

The present embodiments are generally directed to annular blowout preventers (BOPs). Annular BOPs may include a packer assembly (e.g., an annular packer assembly) disposed within a housing (e.g., an annular housing). A piston (e.g., annular piston) may be adjusted in a first axial direction to drive the packer assembly from an open position to a closed position to seal an annulus around a tubular member disposed through a central bore of the annular BOP or to close the central bore. In certain disclosed embodiments, the packer assembly includes a packer (e.g., annular packer) and one or more inserts (e.g., rigid inserts) coupled to, or formed within, the packer. In some embodiments, a first set of inserts may be arranged in a configuration that facilitates an annular type closing of the packer assembly (e.g., the inserts move axially upward and radially inward to contact one another). Additionally, a second set of inserts may be arranged in a configuration that facilitates an “iris-style” closing similar to that of an iris shutter of a camera. In certain embodiments, the second set of inserts are positioned beneath the first set of inserts to provide support to the first set of inserts and/or the packer. In other embodiments, the packer assembly may not include the second set of inserts, and instead, include an annular ring support disposed beneath the first set of inserts to support the first set of inserts and/or the packer. As discussed in more detail below, the disclosed embodiments may reduce extrusion of the packer as the annular BOP moves from the open position to the closed position, thereby reducing wear on components of the annular BOP, for example.

With the foregoing in mind, FIG. 1 is a block diagram of an embodiment of mineral extraction system 10. The illustrated mineral extraction system 10 may be configured to extract various minerals and natural resources, including hydrocarbons (e.g., oil and/or natural gas), from the earth, or to inject substances into the earth. The mineral extraction system 10 may be a land-based system (e.g., a surface system) or an offshore system (e.g., an offshore platform system). As shown, a BOP assembly 16 (e.g., BOP stack) is mounted to a wellhead 18, which is coupled to a mineral deposit via a wellbore 26. The wellhead 18 may include any of a variety of other components such as a spool, a hanger, and/or a “Christmas” tree. The wellhead 18 may return drilling fluid or mud to the surface 12 during drilling operations, for example. Downhole operations are carried out by a tubular string 24 (e.g., drill string, production tubing string, or the like) that extends, through the BOP assembly 16, through the wellhead 18, and into the wellbore 26.

To facilitate discussion, the BOP assembly 16 and its components may be described with reference to an axial axis or direction 30, a radial axis or direction 32, and a circumferential axis or direction 34. The BOP assembly 16 may include one or more annular BOPs 42 and/or one or more ram BOPs (e.g., shear ram, blind ram, blind shear ram, pipe ram, etc.). A central bore 44 (e.g., flow bore) extends through the one or more annular BOPs 42. As discussed in more detail below, each of the annular BOPs 42 includes a packer assembly (e.g., annular packer assembly) that is configured to be mechanically squeezed radially inwardly to seal about the tubular string 24 extending through the central bore 44 (e.g., to block an annulus about the tubular string 24) and/or to block flow through the central bore 44. The disclosed embodiments include annular BOPs 42 with a packer assembly having various features, such as one or more inserts coupled to a packer in a configuration that facilitates an annular style closing and/or an “iris-style” closing.

FIG. 2 is a cross-sectional side view of the annular BOP 42 that may be used in the system 10 of FIG. 1. In the illustrated embodiment, the annular BOP 42 and the components therein are in an open position 50. In the open position 50, fluid may flow through the central bore 44 of the annular BOP 42. The annular BOP 42 includes a housing 54 (e.g., annular housing) having a body 56 and a top 58 (e.g., top portion or top component) coupled to and/or disposed partially within the body 56. A piston 60 (e.g., annular piston) and a packer assembly 52 (e.g., annular packer assembly) are positioned within the housing 54. The packer assembly 52 includes a packer 62 (e.g., an annular packer), a first set of inserts 64 (e.g., annularly arranged inserts) positioned circumferentially about the packer 62, and/or a second set of inserts 66 (e.g., iris support inserts) positioned circumferentially about the packer 62. As shown in the illustrated embodiment of FIG. 2, the second set of inserts 66 are disposed axially below the first set of inserts 64 with respect to the axis 30 defining the central bore 44. In certain embodiments, the packer 62 is a flexible component (e.g., elastomer or rubber) and the first set of inserts 64 and the second set of inserts 66 are rigid (e.g., metal, metal alloy, or a rigid polymeric material). An adapter 68 (e.g., annular adapter) is positioned between the body 56 and the top 58. Various seals 70 (e.g., annular seals) may be provided in the body 56, the piston 60, and/or the adapter 68 to seal chambers 72, 74 (e.g., annular chambers) from the central bore 44 and from one another.

As discussed in more detail below, the piston 60 is configured to move relative to the housing 54 in the axial direction 30. For example, a fluid (e.g., a liquid and/or gas) may be provided to the chamber 72 via a first fluid conduit 76 to drive the piston 60 upwardly in the axial direction 30, as shown by arrow 78. As the piston 60 moves upwardly, the piston 60 drives the packer 62 upwardly. For example, an axially-facing surface 80 (e.g., e.g., packer-contacting surface, top surface, upper surface, or annular surface) of the piston 60 may apply an upward force against an axially-facing surface 82 (e.g., piston-contacting surface, bottom surface, lower surface, or annular surface) of the packer 62, driving the packer upwardly in the axial direction. When driven upwardly by the piston 60, the packer 62 may move upwardly in the axial direction and inwardly in the radial direction within the top 58 to a closed position in which the packer 62 seals around the tubular string 24 extending through the central bore 44 and/or blocks fluid through the central bore 44. In some embodiments, a second fluid conduit 84 is configured to provide a fluid (e.g., a liquid and/or gas) to the chamber 74 to drive the piston 60 downwardly in the axial direction, thereby causing the packer 62 to move from the closed position to the open position 50.

In the illustrated embodiment, the packer assembly 52 includes the packer 62, the first set of inserts 64, and/or the second set of inserts 66. The second set of inserts 66 may support the packer 62 and/or the first set of inserts 64 and may facilitate an “iris-style” closing to enable the packer assembly 62 to move inwardly in the radial direction from the open position 50 to the closed position. As shown, the first set of inserts 64 and the second set of inserts 66 are coupled to the packer 62 and are positioned circumferentially about the packer 62 (e.g., at discrete locations circumferentially about the packer 62). The first set of inserts 64 are configured to contact a radially-inner surface 86 (e.g., curved annular surface, dome-shaped surface, or semi-spherical surface) of the top 58, and are in an expanded position 88 while the annular BOP 42 is in the open position 50. In the expanded position 88, respective end portions 90 (e.g., radially-inner and/or upper end portions or tips) of adjacent inserts 64 are separated by a first distance 92 (e.g., along the circumferential axis 34). Additionally, opposed respective end portions of opposed inserts 66 (e.g., diametrically opposed on opposite sides of the central bore 44) define a first diameter 96 (e.g., along the radial axis 32). In certain embodiments, the distance between respective end portions 90 of adjacent inserts 64 and the distance between respective end portions 94 of opposed inserts 66 may decrease as the annular BOP 42 moves from the open position 50 to the closed position.

In the illustrated embodiment, the first set of inserts 64 and the second set of inserts 66 do not directly contact the piston 60 while the annular BOP 42 is in the open position 50. For example, the packer 62 may be positioned between the second set of inserts 66 and the piston 60 along the axial axis 30, and the second set of inserts 66 is separated from the axially-facing surface 82 of the packer 62 and/or the axially-facing surface 80 of the piston 60 by an axial distance. While the annular BOP 42 is in the open position 50, the axial distance may be equal to or greater than approximately 1, 2, 5, 10, 20, 30, 40, or 50 percent of a total height 100 (e.g., along the axial axis) of the packer assembly 52. In certain embodiments, the first set of inserts 64 and the second set of inserts 66 do not directly contact the piston 60 while the annular BOP 42 is in the open position 50, the closed position, or any position therebetween. However, in some embodiments, the second set of inserts 66 and the piston 60 may contact one another while the annular BOP 42 is in the open position 50, the closed position, and/or a position therebetween.

FIG. 3 is a cross-sectional side view of the annular BOP 42 in a closed position 110. As shown in the illustrated embodiment of FIG. 3, the piston 60 is driven along the axial direction 30 via pressurized fluid directed into the chamber 72. As such, the axially-facing surface 80 of the piston 60 contacts the axially-facing surface 82 of the packer 62 to drive the packer 62 into the closed position 110. As shown in the illustrated embodiment, the first set of inserts 64 contact the radially-inner surface 86, such that the first set of inserts 64 are directed radially inward along the axis 32 to contact one another and seal the wellbore 26. In other words, the radially-inner surface 86 forms a semi-spherical surface that acts as a cam surface to direct the first set of inserts 64 radially inward along the axis 32. For example, the respective end portions 90 of the first set of inserts 64 may be positioned proximate to, or in contact with, the tubular string 24 disposed in the central bore 44. Additionally, the first diameter 96 between diametrically opposed inserts 64 decreases as the annular BOP 42 transitions from the open position 50 to the closed position 110. The first set of inserts 64 thus move radially inward along the axis 32 and into contact with the tubular string 24 in the central bore 44. Thus, the first set of inserts 64 may form a seal within the central bore 44 around the tubular 112.

Further, while the packer 62 of the packer assembly 52 is transparent in the illustrated embodiment of FIG. 3, the packer 62 may compress against the radially-inner surface 86 and further enhance the seal about the tubular string 24 within the central bore 44. Further still, the second set of inserts 66 may also engage the tubular string 24 to seal the central bore 44. For example, the second set of inserts 66 may close about the tubular 112 in a manner resembling an iris shutter of a camera. In some embodiments, the second set of inserts 66 rotate radially inwardly (e.g., move along a spiral or parabolic path toward the center of the central bore 44). As the packer 62 compresses within the housing 54 of the annular BOP 42, the packer 62 directs the second set of inserts 66 radially inward along the axis 32 toward the center of the central bore 44. For instance, a first surface (e.g., side surface) of one insert of the second set of inserts 66 may move along a second surface (e.g., side surface) of an adjacent insert of the second set of inserts 66 to enable the second set of inserts 66 to maintain contact with one another during the transition between the open position 50 and the closed position 110. The second set of inserts 66 may also move toward the tubular string 24 in order to form a seal around the tubular string 24 within the central bore 44. Accordingly, the packer assembly 52 may form the seal within the central bore 44 and around the tubular string 24 using the packer 62, the first set of inserts 64, and the second set of inserts 66.

FIG. 4 is a perspective view of an embodiment of the packer assembly 52. As shown in the illustrated embodiment, the first set of inserts 64 and the second set of inserts 66 are formed into the packer 62. In some embodiments, the packer 62 may include an elastomeric material (e.g., rubber) that is molded into a specific shape that conforms to the top 58 (e.g., the radially-inner surface 86) of the housing 54. The first set of inserts 64 and/or the second set of inserts 66 may be included in the mold, such that the packer 62 is integrally formed around the first and second set of inserts 64, 66. In other embodiments, the packer 62 may be formed with one or more openings that enable the first and/or the second set of inserts 64, 66 to be inserted into the packer 62. In any case, the packer assembly 52 is configured to form the seal around the tubular string 24 using the packer 62 (e.g., compresses against the tubular string 24 and/or the radially-inner surface 86), the first set of inserts 64 (e.g., move radially inward such that the respective end portions 90 contact the tubular string 24 form a seal), and/or the second set of inserts 66 (e.g., move radially inward using an iris-style technique to contact one another and/or the tubular string 24 to form the seal).

In some embodiments, the first set of inserts 64 and the second set of inserts 66 are separate components from one another. As such, the first set of inserts 64 and the second set of inserts 66 may move independently of one another. In other words, movement of the first set of inserts 64 does not cause movement of the second set of inserts 66, and vice versa. In such embodiments, movement (e.g., compression) of the packer 62 causes both the first set of inserts 64 and the second set of inserts 66 to move within the housing 54 of the annular BOP 42. In other embodiments, the first set of inserts 64 and the second set of inserts 66 may be coupled to one another via fasteners (e.g., threaded bolts and nuts), welds, and/or another suitable coupling technique. In still further embodiments, a first insert of the first set of inserts 64 and a second insert of the second set of inserts 66 may be formed as a single, unitary component. In other words, the first insert of the first set of inserts 64 may be integrated with the second insert of the second set of inserts 66. Further still, each insert of the first set of inserts 64 may be separate from one another, such that the inserts of the first set of inserts 64 are not linked or coupled to one another. Additionally, each insert of the second set of inserts 66 may be separate from one another, such that the inserts of the second set of inserts 66 are not linked or coupled to one another. Thus, each insert of the first set of inserts 64 and each insert of the second set of inserts 66 may move independent from the remaining inserts of the first set of inserts 64 and the second set of inserts 66, respectively. In other embodiments, some or all of the inserts of the first set of inserts 64 and/or some or all of the inserts of the second set of inserts 66 may be coupled or linked to one another.

The first set of inserts 64 are configured to move along the axis 30 toward the radially-inner surface 86. As the first set of inserts 64 contact the radially-inner surface 86, the first set of inserts 64 may begin to move radially inward along the axis 32 toward one another. The radially-inner surface 86 may gradually angle, taper, and/or curve toward the axis 30, such that the first set of inserts 64 are driven radially inward as the piston 60 drives the packer assembly 52 axially against the radially-inner surface 86. In other words, the radially-inner surface 86 acts as a cam and/or a wedge that drives the first set of inserts 64 radially inward along the axis 32 toward one another. As such, the first set of inserts 64 may contact one another (e.g., at least circumferentially facing side surfaces of adjacent inserts of the first set of inserts 64 contact one another). As shown in the illustrated embodiment of FIG. 4, the first set of inserts 64 each include a body portion 114 (e.g., a tapered body portion). The body portion 114 may include a geometry that enables side surfaces 115 of the first set of inserts 64 to contact one another, such that circumferential gaps 116 formed between adjacent inserts of the first set of inserts 64 are closed to form the seal within the wellbore 26 (e.g., the central bore 44 of the annular BOP 42). Further, the diameter 96 between diametrically opposed inserts of the first set of inserts 64 is reduced as the annular BOP 42 moves toward the closed position 110, such that the first set of inserts 64 are positioned proximate to or in contact with the tubular string 24. Accordingly, the first set of inserts 64 are configured to form the seal via an axial force that is applied to the packer assembly 52 by the piston 60.

Additionally, when transitioning between the open position 50 and the closed position 110, the second set of inserts 66 may not move along the axis 30, but move radially inward along the axis 32. For example, in the open position 50, each insert of the second set of inserts 66 may be in contact with one another in a first position 118, as shown in FIG. 4. As the piston 60 moves axially upward along the axis 30 as shown by arrow 78 in FIGS. 2 and 3, the packer 62 may begin to compress causing the second set of inserts 66 to move radially inward along the axis 32. As such, each insert of the second set of inserts 66 may extend radially inward toward the central bore 44. As the second set of inserts 66 rotate and/or otherwise move radially inward toward the central bore 44 (e.g., rotate radially inward along a spiral or parabolic path), adjacent inserts of the second set of inserts 66 may maintain contact with one another while reducing a diameter 120 of an opening 122 formed by the second set of inserts 66. In some embodiments, no gaps are present between adjacent inserts of the second set of inserts 66 during the transition between the open position 50 and the closed position 110.

As set forth above, the second set of inserts 66 may reduce the diameter 120 of the opening 122 formed by the second set of inserts 66 when the piston 60 is actuated to move the packer assembly 52 to the closed position 110. The second set of inserts 66 may thus provide structural support to the packer 62 as the packer 62 compresses within the housing 54 of the annular BOP 42. For example, the second set of inserts 66 move radially inward, and thus establish a barrier and/or support that blocks the packer 62 from compressing in a downward direction (e.g., represented by arrow 124) along the axis 30. In other words, the second set of inserts 66 may block the packer 62 from compressing and/or otherwise moving into the opening 122. As such, extrusion of the packer 62 may be reduced as a result of an increased surface area provided by the second set of inserts 66 in the closed position 110, thereby increasing an operational life of the packer assembly 52.

FIG. 5 is a perspective view of an embodiment of a first insert 130 of the first set of inserts 64 and a second insert 132 of the second set of inserts 66. As shown in the illustrated embodiment, the first insert 130 may include a rounded portion 134 (e.g., a curved pivot portion or rotational bearing portion) that is configured to enable movement of the first insert 130 with respect to the second insert 132. For example, in some embodiments, the first insert 130 may rotate about a rotational axis 136 as the piston 60 applies an axial force to the packer 60. The first insert 130 may contact the radially-inner surface 86 (e.g., dome-shaped surface), thereby directing the first insert 130 radially inward into the central bore 44 and rotating the first insert 130 about the axis 136. Accordingly, the rounded portion 134 may be configured to reduce any restriction to the rotational movement of the first insert 130 with respect to the second insert 132. For instance, replacing the rounded portion 134 with a substantially polygonal shape (e.g., rectangular) may restrict movement caused by contact between the first insert 130 and a surface 138 of the second insert 132. Therefore, the rounded portion 134 facilitates movement of the first insert 130 with respect to the second insert 132 and enables the first insert 130 to contact adjacent inserts of the first set of inserts 64 to form the seal within the central bore 44.

Additionally, the first insert 130 may include a sealing portion 140 that includes the respective end portion 90. As set forth above, the sealing portion 140 may include a tapered geometry (e.g., a wedge-shaped or pie-shaped sealing portion) to enable contact between adjacent inserts of the first set of inserts 64 when the packer assembly 52 is in the closed position 110.

Additionally, the sealing portion 140 may include a curvature that generally corresponds to a curvature of the radially-inner surface 86 of the top 58 the housing 54. Further still, the first insert 130 may include a coupling portion 142 (e.g., a leg portion) that extends between and couples the rounded portion 134 and the sealing portion 140 to one another. In some embodiments, the coupling portion 142 and/or the rounded portion 134 are configured to be disposed within a body of the packer 62 and the sealing portion 140 is configured to be positioned external to or flush with the body of the packer 62. As such, the sealing portion 140 may be configured to directly contact the radially-inner surface 86, which may cause rotational movement of the rounded portion 134 and/or the coupling portion 142.

The second insert 132 may be configured to move radially inward along the axis 32 as the packer 62 compresses due to the axial force exerted on the packer 62 by the piston 60. For instance, the second insert 132 includes a support portion 146 and an iris portion 148. In some embodiments, the support portion 146 is configured to be positioned proximate to and/or in contact with the rounded portion 134 of the first insert 130. The support portion 146 may include the surface 138 configured to support the first insert 130 and enable movement of the rounded portion 134 of the first insert 130 as the packer assembly 52 transitions between the open position 50 and the closed position 110. Further, the support portion 146 is configured to move radially inward within the central bore 44 (e.g., rotate radially inward along a spiral or parabolic path) as the packer 62 compresses within the central bore 44 as a result of the axial force applied by the piston 60. In some embodiments, the packer 62 contacts the radially-inner surface 86 and/or other surfaces within the housing 54 and compresses. Compression of the packer 62 then exerts a force on the second insert 132 causing the support portion 146 to move radially inward along the axis 32 and thus direct the iris portion 148 radially inward within the central bore 44. As the iris portion 148 moves radially inward within the central bore 44, the diameter 120 of the opening 122 formed by the second set of inserts 66 is reduced. Accordingly, each insert of the second set of inserts 66 move radially inward along the axis 32 to increase a radial surface area formed by the second set of inserts 66 that supports the packer 62. As such, a surface and/or barrier formed by the second set of inserts 66 is configured to block movement of the packer 62 in a downward direction along the axis 30 (e.g., in an opposite direction of arrow 78 shown in FIGS. 2 and 3). Blocking the packer 62 from moving in the downward direction along the axis 30 may reduce extrusion incurred by the packer 62, which may prolong an operational life of the packer assembly 52.

FIG. 6 is a perspective view of another embodiment of the packer assembly 52 having the packer 62, the first set of inserts 64, and a second set of inserts 160. In the illustrated embodiment of FIG. 6, the first set of inserts 64 may be substantially the same as the first set of inserts 64 of the embodiment of FIGS. 2-5, but the second set of inserts 160 may include a different configuration from the second set of inserts 66 of FIGS. 2-5. For example, FIG. 7 is a perspective view of the packer assembly 52 of FIG. 6 with the packer 62 shown as transparent to illustrate the second set of inserts 160.

The second set of inserts 160 may include a support portion 162 and an iris portion 164 similar to the second set of inserts 66 set forth above. As shown in the illustrated embodiment of FIG. 6, the support portion 162 and the iris portion 164 are substantially planar (e.g., positioned within substantially a single plane 166), as opposed to the second set of inserts 66 that includes the support portion 146 having a reduced height or thickness when compared to the iris portion 148. Including the support portion 162 and the iris portion 164 in the planar configuration may facilitate manufacturing of the second set of inserts 160 and/or reduce manufacturing costs of the packer assembly 52.

In some embodiments, the iris portion 164 of the second set of inserts 160 may include grooves 168 that are configured to increase friction between the packer 62 and the second set of inserts 160. For instance, the grooves 168 may cause the packer 62 (e.g., having an elastomeric material such as rubber) to maintain contact with the second set of inserts 160 as the packer assembly 52 transitions between the open position 50 and the closed position 110.

Accordingly, the packer 62 may stick to and/or otherwise maintain contact with the second set of inserts 160 to further reduce extrusion of the packer 62 (e.g., the packer 62 maintains contact with the second set of inserts 160 rather than collapsing into the opening 122). In any case, the support portion 162 of the second set of inserts 160 may be directed radially inward along the axis 32 within the central bore 44 (e.g., rotate radially inward along a spiral or parabolic path), thereby causing the iris portion 164 to move radially inward along the axis 32 within the central bore 44. As should be understood, each iris portion 164 of the second set of inserts 160 may be configured to maintain contact with iris portions 164 of adjacent inserts while moving radially inward along the axis 32. Accordingly, the diameter 120 of the opening 122 formed by the second set of inserts 66 is reduced without forming circumferential gaps between inserts of the second set of inserts 160. The second set of inserts 160 thus forms a surface and/or barrier that blocks movement of the packer 62 into the opening 122, thereby reducing extrusion of the packer 62.

FIG. 8 is a perspective view of a first insert 180 of the first set of inserts 64 and a second insert 182 of the second set of inserts 160. As shown in the illustrated embodiment of FIG. 8, the first insert 180 includes a rounded portion 184, a sealing portion 186, and a coupling portion 188 similar to the first insert 130 set forth above. For instance, the rounded portion 184 (e.g., pivot portion or rotational bearing portion) is configured to rotate about a rotational axis 190 as the packer assembly 52 is driven toward the closed position 110 by the piston 60. The sealing portion 186 may be configured to contact the radially-inner surface 86 causing rotation of the rounded portion 184 about the rotational axis 190. Further the sealing portion 186 includes a tapered geometry (e.g., wedge-shaped portion or pie-shaped portion) configured to facilitate movement of the first insert 180 along the axis 30 with respect to adjacent inserts of the first set of inserts 64. In some embodiments, the tapered geometry of the sealing portion 186 includes a radius of curvature that is substantially equal to (e.g., within 10% of, within 5% of, or within 1% of) a radius of curvature of the radially-inner surface 86. Additionally, the tapered geometry of the sealing portion 186 may enable adjacent inserts of the first set of inserts 64 to contact one another (e.g., via circumferentially facing side surfaces of the respective sealing portions 186) and form a seal when the packer assembly 52 is in the closed position 110.

As set forth above, the second insert 182 includes a support portion 162 and an iris portion 164 that are positioned within substantially the same plane 166. Further, the iris portion 164 of the second insert 182 includes the grooves 168 that are configured to maintain contact between the packer 62 and the second set of inserts 160 to further reduce extrusion of the packer 62. In some embodiments, the support portion 162 includes a rounded edge 192. The rounded edge 192 may facilitate movement of the second insert 182 radially inward along the axis 32 (e.g., rotational movement along the spiral or parabolic path) with respect to adjacent inserts of the second set of inserts 160. For example, the rounded edge 192 may urge and/or bias the second insert 182 toward an adjacent insert of the second set of inserts 160 as the second set of inserts 160 move radially inward along the axis 32 within the central bore 44. In any case, the second set of inserts 160 is configured to reduce the diameter 120 of the opening 122 formed by the second set of inserts 160 to provide support and/or a barrier that blocks the packer 62 from compressing and/or otherwise moving into the opening 122, thereby reducing extrusion and extending an operating life of the packer assembly 52.

FIG. 9 is a perspective view of another embodiment of the packer assembly 52. As shown in the illustrated embodiment of FIG. 9, the packer assembly 52 includes the packer 62 (shown as transparent in FIG. 9), the first set of inserts 64, and a support ring 200 (e.g., an annular support). Thus, the packer assembly 52 of FIG. 9 includes the support ring 200 instead of the second set of inserts 66, 160. Including the support ring 200 may facilitate manufacturing of the packer assembly 52 and/or reduce manufacturing costs by reducing an amount of components included in the packer assembly 52. The support ring 200 includes an opening 202 that has a diameter 204. In some embodiments, the diameter 204 may be substantially the same as the diameter 120 of the opening 122 formed by the second set of inserts 66, 160 when the packer assembly 52 is in the closed position 110. While the support ring 200 may move along the axis 30 as the packer assembly 52 transitions from the open position 50 to the closed position 110, the support ring 200 does not move radially inward or outward (e.g., along the axis 32). Therefore, the support ring 200 maintains a shape and/or structure as the packer assembly 52 transitions between the open position 50 and the closed position 110. The support ring 200 may function similar to the second set of inserts 66, 160 set forth above. For example, the support ring 200 is configured to block and/or otherwise support the packer 62 to reduce extrusion. Thus, the support ring 200 includes a surface 206 that is configured to block movement of the packer 62 into the opening 202 to reduce extrusion of the packer 62, and thus, increase an operating life of the packer assembly 52. In the context of this disclosure, the support ring 200 and the second set of inserts 66, 160 each may be considered an extrusion protection ring, an extrusion blocking insert, and/or a barrier insert.

In some embodiments, the support ring 200 includes a metal material, such as steel, stainless steel, aluminum, and/or another suitable metal. In other embodiments, the support ring 200 includes a non-metallic material, such as a polymeric material, a ceramic material, and/or another suitable non-metallic material. Additionally, the support ring 200 may include a variable thickness. For example, the support ring 200 may include a first thickness at the diameter 204 (e.g., an inner diameter defining the opening 202) and a second thickness at an outer diameter 208 of the support ring 200 (e.g., a diameter of the entire structure of the support ring 200). In some embodiments, the first thickness may be less than the second thickness. In other embodiments, the first thickness may be greater than the second thickness. Additionally or alternatively, the thickness of the support ring 200 may gradually increase or decrease from the first thickness to the second thickness in the radial direction from the diameter 204 to the outer diameter 208. While the illustrated embodiment of FIG. 9 shows the support ring 200 as a ring-shaped (e.g., annular) component, in other embodiments, the support ring 200 may include any suitable shape and/or cross sectional shape (e.g., triangular, square, rectangular, pentagonal, hexagonal, heptagonal, octagonal, or another suitable shape). The support ring 200 may include a solid structure and/or material or a semi-hollow, textured, and/or webbed structure. In any case, the support ring 200 includes a connected structure that provides support to the packer 62 to reduce extrusion of the packer 62 into the opening 202.

While the disclosure may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the disclosure is not intended to be limited to the particular forms disclosed. Rather, the disclosure is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure as defined by the following appended claims. 

1. A packer assembly for an annular blowout preventer, comprising: an annular packer; a plurality of inserts arranged circumferentially about the annular packer, wherein the plurality of inserts is configured to move radially inward to enable the packer assembly to move from an open position in which the packer assembly enables fluid flow through a central bore to a closed position in which the packer assembly blocks fluid flow through the central bore; and a support positioned below the plurality of inserts with respect to a height of the packer assembly, wherein the support is configured to block at least a portion of the annular packer from moving into an opening extending through the packer assembly in the closed position.
 2. The packer assembly of claim 1, wherein the annular packer comprises a flexible material and the plurality of inserts comprise a rigid material.
 3. The packer assembly of claim 1, wherein the support comprises a second plurality of inserts arranged circumferentially about the annular packer, wherein the second plurality of inserts is configured to rotate radially inward to enable the packer assembly to move from the open position to the closed position.
 4. The packer assembly of claim 3, wherein the second plurality of inserts is configured to rotate radially inward along a spiral path to enable the packer assembly to move from the open position to the closed position.
 5. The packer assembly of claim 3, wherein each insert of the second plurality of inserts comprises a support portion and an iris portion, and wherein the support portion and the iris portion are substantially planar.
 6. The packer assembly of claim 5, wherein the iris portion comprises grooves configured to increase friction between the second plurality of inserts and the annular packer.
 7. The packer assembly of claim 1, wherein the support comprises an annular ring.
 8. The packer assembly of claim 7, wherein the annular ring comprises a solid, metallic material or a solid, non-metallic material.
 9. The packer assembly of claim 7, wherein the annular ring is configured to maintain a geometry as the packer assembly moves from the open position to the closed position.
 10. The packer assembly of claim 1, wherein the plurality of inserts and the support are configured to be molded into the annular packer.
 11. The packer assembly of claim 1, wherein the plurality of inserts and the support are configured to move independently of one another.
 12. An annular blowout preventer, comprising: a housing; an annular piston positioned within the housing; and a packer assembly positioned within the housing, wherein the packer assembly comprises: an annular packer; a plurality of inserts arranged circumferentially about the annular packer; and a support positioned axially below the plurality of inserts with respect to a height of the packer assembly; wherein the annular piston is configured to contact a surface of the annular packer to drive the packer assembly in an axial direction within the housing, thereby compressing the annular packer, causing the plurality of inserts to move radially inward, and moving the annular blowout preventer to a closed position, and wherein the support is configured to block at least a portion of the annular packer from moving into an opening extending through the packer assembly in the closed position.
 13. The annular blowout preventer of claim 12, wherein each insert of the plurality of inserts is configured to contact a wall of the housing to direct movement of each insert of the plurality of inserts radially inward.
 14. The annular blowout preventer of claim 13, wherein each insert of the plurality of inserts comprises a curved radially-outer surface that includes a first radius of curvature that is substantially the same as a second radius of curvature of the wall of the housing.
 15. The annular blowout preventer of claim 12, wherein the annular packer is positioned between the support and the piston along an axial axis of the annular blowout preventer, thereby blocking contact between the support and the piston while the annular blowout preventer is in the open position, the closed position, and any position therebetween.
 16. The annular blowout preventer of claim 12, wherein the support comprises a second plurality of inserts arranged circumferentially about the annular packer, wherein the second plurality of inserts is configured to rotate radially inward to enable the packer assembly to move from the open position to the closed position.
 17. The annular blowout preventer of claim 12, wherein the support comprises an annular ring.
 18. A system, comprising: a packer assembly, comprising: an annular packer; a first plurality of inserts arranged circumferentially about a first axial end portion of the annular packer; and a second plurality of inserts arranged circumferentially about the annular packer proximate to a second axial end portion of the annular packer; wherein the first plurality of inserts and the second plurality of inserts are configured to move radially inwardly as the packer assembly moves from an open position in which the packer assembly enables fluid flow through a central bore to a closed position in which the packer assembly blocks fluid flow through the central bore, and the second plurality of inserts is configured to block at least a portion of the annular packer from moving into an opening extending through the packer assembly in the closed position.
 19. The system of claim 18, wherein the second plurality of inserts is configured to form a first radial surface area in the open position and configured to form a second radial surface area in the closed position, wherein the second radial surface area is greater than the first radial surface area.
 20. The system of claim 18, wherein the second plurality of inserts is configured to rotate radially inward along a spiral path to enable the packer assembly to move from the open position to the closed position. 